Preparation Of Phosphate Polyvinyl Alcohol And Research Of Biomineralization In Vitro

Biomineralization is an extremely delicate process which the organic matrix involvedin throughout. In this process, the carbonic acid, phosphoric acid, etc. possessingnegatively charged groups in the macromolecular matrix have the function ofconcentrating calcium ions, adjusting mineral nucleation and growth by electrostaticinteraction. As a commonly used water-soluble polymer, polyvinyl alcohol (PVA) hasbeen widely used in biomaterials. This article will focus on its derivatives Phosphatepolyvinyl alcohol (PPVA), and prepare a series of PPVA with different phosphorus contentas well as PPVA/hydroxyapatite composite porous hydrogel. This may be expected to beused for bone tissue repair.Two methods have been used for obtaining PVA with different phosphation degrees.A higher degree of esterification which was more than20%of PPVA can be achievedwhen using DMF instead of water as solvent reaction system. The viscosity and the tensilestrength of the resultant PPVA both reduced when the degree of esterification increasing.It was to be found that PPVA films with the degree of esterification had mineralizedby the change of mass, PH, calcium and phosphorus content, XRD, SEM. The conclusionwas the extent of this mineralization increased with an increasing of the degree ofesterification, and the PVA film did not mineralized almost. The EDX spectrum shows thecalcium phosphate molar ratio of formed inorganics was1.57which was close to1.67belonging to hydroxyapatite.In addition, a needle-like HA obtained which was about40-60nm and was close tothe size of HA in the mature bone tissue in situ synthesis in the presence of PPVA. Whenadding the surfactant OP and rapidly stirring in advance, a more than90%moisture content along with a certain mechanical strength of biodegradable PPVA/HA porouscomposite was prepared. This gel material has the potential to become a new bone tissuerepair material.